Automatic starting-switch.



Patented June 10,1913.

lrpventon Charles D. Kni

Wmesses:

gm. M

COLUMBIA pumoclulm 420-. WASHINGTON. 0. c4

UNITED STATES PATENT OFFICE.

CHARLES D. KNIGHT, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERALELECTRIC COMPANY, A CORPORATION OF NEW YORK.

AUTOMATIC STARTING-SWITCH.

Application filed December 1, 1905.

To all whom it may concern:

Be it known that I, CHARLES D. KNIGHT, a citizen of the United States,residing at Schenectady, county of Schenectady, State of New York, haveinvented certain new and useful Improvements in AutomaticStarting-Switches, of which the following is a specification.

My invention relates to starting switches for electric motors, and itsobject is to provide a novel and etlicient apparatus for automaticallyestablishing the proper circuit connections for a motor for starting andfor running, with proper time-intervals between the changes in thecircuit connections; the apparatus being controlled by a simple switchor contact-maker. r

By means of my invention a motor may be properly connected for starting,and when it is up to speed the proper connections for runningautomatically established; the apparatus being controlled by a simplecontact-maker, which may be actuated either manually orautomatically,as, for instance, by a fluid-pressure governor.

My invention is particularly applicable to the control ofalternating-current motors, such as induction motors withshort-circuited secondary, which are started by lowering the impressedprimary voltage, although it is not limited to this particularapplication.

My invention in one aspect consists in the combination of a switchrotatable continuously in the same direction, and having anofl"-position and a plurality of operative positions, operating meansadapted to move the switch step by step, controlling means adapted whenactuated to energize the operating means automatically a predeterminednumber of times at predetermined intervals, and means for energizing theoperating means independently of the controlling -means so as to shiftthe switch from the last to its several operative positions, and uponSpecification of Letters Patent.

Patented June 10, 1913.

Serial No. 289,775.

the closing of a second electric circuit shifting it from the lastoperative position to off-position.

More specifically stated, my invention consists in the combination of aswitch rotatable continuously in the same direction and having anoff-position and a plurality of operative positions, an electromagnetfor operating said switch, ratchet connections between the switch andcontrolling magnet,

means controlled by the controlling magnet when energized to shift theswitch step by step from off to starting and then to running position,:and means for retarding the operation of the operating means.

My invention further comprises means for automatically denergizing' theoperating means upon the movement of the switch so as to save loss ofpower, and means for again energizing the operating meansto continue themovement of the switch'from running to off-position when it is desiredto stop the motor. p

My invention will best be understood by reference to the in which-Figure 1 shows diagrammatically a motor provided with automatic startingand controlling apparatus arranged in accordance with my invention; Fig.2 shows another view of the same with the mechanical connections betweenthe operating means and the switch omitted and with the switch contactsdeveloped on a plane surface; Fig. 3 shows a detail of the connectionsbetween the operating magnet and the switch and Fig. 4 is a detail ofthe dash-pot.

In the drawings, A represents an alternating-current induction-motorwhich is connected through the controlling switch B to avoltage-controlling device, such as a compensator C, which is suppliedfrom the source of three-phase current indicated by accompanyingdrawings,

the line-wires D. At starting the motor is connected to intermediatepoints on the compensator winding, and in running is connected directlyto the line. The switch B is mounted so that it is continuouslyrot-atable in the same direction, and is actuated by a ratchet mechanismconsisting of a pivoted bar E, which is raised every time the operatingmagnet F is energized, and lugs b on the switch which are adapted to beengaged by the pivoted bar E. Every time the bar E is raised it rotatesswitch B one hundred and twenty degrees. Three lugs 7) are provided, andare so arranged, as shown in Fig. 3, that the bar E in falling, whenreleased by the operating magnet, slides over and engages the undersideof a lug so that it is ready to shift the switch again when theoperating magnet is again energized. The operating magnet F iscontrolled by a controlling magnet G which, when energized, is arrangedto close and break the circuit of the operating magnet a predeterminednumber of times at predetermined intervals. The said number of timescorresponds to the number of operative positions of switch B, and in thecase shown is consequently two. The closing and breaking of the circuitof magnet F is accomplished by a pair of switch contacts H and H carriedby the core of magnet G which are adapted to engage the contacts h and hrespectively. The desired time-interval is obtained by means of adash-pot I connected'to the core of the controlling magnet G. Thecontrol ling magnet is in turn controlled by a master-switch S, which isadapted to engage the contact 8 to close one circuit for starting, or toengage the second contacts to close another circuit for stopping themotor. The switch S may be a simple manuallyoperated switch, or may becontrolled by a fluid-pressure governor or any other automatic device.

The operation of the apparatus above described is as follows:Atst-arting, the switch Bis in off-position and the motor circuit isbroken as is shown in Fig. 2. To start the motor the switch S is movedinto engagement with contact 8. A circuit is then closed through switchS, contact 8, contacts carried by switch B, and controlling magnet G.Controlling magnet G is consequently energized and draws up its core.The dashpot is preferably arranged so as to exert no retarding effectwhen the core is raised, butonly to retard the downward movement of thecore. \V hen the core of controlling magnet G reaches its highestposition the switch contact H bridges the stationary contact h, therebyclosing a circuit through the operating magnet F. This magnetconsequently draws up the pivoted bar E and shifts switch B one hundredand twenty degrees, thereby connecting the motor it to intermediatepoints on the winding of compensator C, as is evident from an inspectionof other lug b 0n the switch B. The downward movement of the core ofcontrolling magnet G continues, and meanwhile the motor A is speedingup. The dash-pot is so proportioned that when the motor reaches theproper speed the switch contact H bridges the contacts h, thereby againclosing the circuit of operating magnet F through a set of contacts onswitch B, as shown in Fig. 2. again raises pivoted bar E, again rotatingswitch B one hundred and twenty degrees, so as to bring it from startinginto running position. The motoristhen connected so as to receive thefull-line voltage, and at the same time the circuit of operating magnetF is broken at switch B and the pivoted bar E again drops to engage thethird lugb.

The motor is thus brought from. rest up to full speed and proper runningconnections are established with the proper time-interval between thechange in circuit connections; It Will also be not-iced that whenthemotor is thus brought up to speed both operating and controlling magnetsare out.o -circuit so thatthere isno energy wasted-in their windingsduring normal operation.-

The motor continues. in operation. until switch S is moved to engagecontact 8. so as to, close the stopping circuit. This. circuitextends-from contact 8 through a pair of contacts on switch B, which areclosed in running position, and through/operating magnet F. Theoperating magnet consequently is again energized and rotates switch Banother one hundred and twenty degrees, which brings it from runningback to ofi-position. The motor circuit is thereby broken and the motorstops. At the same time the circuit if operating magnet F is broken atswitch B and the pivoted bar E is again allowed to fall. The apparatusis thus once more in the same condition as at starting, and is ready foragain starting the motor whenever switch S is moved to close thestarting circuit.

For the sake of simplicity I have illustrated my invention somewhatdiagrammatically, and it will be understood that in practice anysuitable construction of switch and operating and controlling magnetsmay be employed.

WV hat I claim as new and desire to secure by Letters Patent of theUnited States, is,

l. In co nbination, a switch rotatable. al-

Operating magnet F ways in the same direction and having an off-positionand a pluralityof operative positions, operating means adapted to movesaid switch step by step, controlling means adapted when actuated toenergize said operating means automatically a predetermined number oftimes at predetermined intervals, and means for energizing saidoperating means independently of said controlling means.

2. In combination, a switch rotatable always in the same direction andhaving an ofi-position and a plurality of operative positions, anelectromagnet for operating said switch, ratchet connections betweensaid switch and said magnet, a controlling magnet, means controlled bysaid control ling magnet for closing and breaking the circuit of saidoperating magnet a predetermined number of times at predeterminedintervals, and means for closing the circuit of the operating magnetindependently of the controlling magnet.

3. In combination, a switch rotatable always in the same direction andhaving an ofi-po-sition and a plurality of operative positions, anoperating magnet, ratchet connections between said switch and saidmagnet, a controlling magnet, a switch actuated by said controllingmagnet and adapted to close and break the circuit of said operatingmagnet a predetermined number of times, and means for retarding themovement of the last-mentioned switch.

at. In. combination, a switch rotatable always in the same direction andhaving an off-position and a plurality of operative positions, anelectromagnet for operating said switch, ratchet connections betweensaid switch and said magnet, a controlling magnet, means controlled bysaid controlling magnet for closing and breaking the circuit of saidoperating magnet a predetermined number of times at predeterminedintervals, means for closing the circuit of the operating magnetindependently of the controlling magnet, and means controlled by themovement of said switch for breaking the circuit of said controllingmagnet.

5. In combination, a switch rotatable always in the same direction andhaving an oft-position and a plurality of operative positions, anelectromagnetfor operating said switch, ratchet connections between saidswitch and said magnet, a controlling 1nag net, means controlled by saidcontrolling magnet for closing and breaking the circuit of saidoperating magnet a predetermined number of times at predeterminedintervals, means for closing the circuit of the operating magnetindependently of the controlling magnet, and switch contacts car ried bysaid switch in circuit with said controlling magnet.

6. In combination, a controlling switch always rotatable in the samedirection and having off, starting, and running positions, an operatingmagnet for said switch, ratchet connections between said magnetand saidswitch, a controlling magnet adapted when energized to make and breakthe circuit of said operating magnet twice at a predetermined interval,and means for closing the circuit of said operating magnet independentlyof said controlling magnet.

7. In combination, a controlling switch always rotatable in the samedirection and having otl, starting, and running posit-ions, an operatingmagnet for said switch, ratchet connections between said magnet and saidswitch, a controlling magnet, means actuated by the movement of the coreof said controlling magnet when energized for closing the circuit of theoperating magnet to move said switch from off to starting position,means for automatically breaking the circuit of the controlling magnetwhen said switch is moved, means actuated by the movement of the core ofthe controlling magnet when denergized for breaking and then againclosing the circuit of the operating magnet to shift said switch torunning position, means for retarding said movement of said core, andmeans for closing the circuit of said operating magnet independently ofsaid controlling magnet to shift said switch to off-position. I

8. In combination, a controlling switch always rotatable in the samehaving ott, starting and running positions, an operating magnet for saidswitch, ratchet connections between said magnet and said switch, acontrolling magnet, means actuated by the movement of the core of saicontrolling magnet when energized for closing the circuit of theoperating magnet to move said switch from off to starting position,means for automatically breaking the circuit of the controlling magnetwhen said switch is moved, means actuated by the movement of the core ofthe controlling magnet when denergized for breaking and then againclosing the circuit of the operat ing magnet to shift said switch torunning position, means for retarding said movement of said core, aswitch adapted to close the circuitof said operating magnetindependentlyof said controlling magnet, and means for automatically breaking thecircuit of the last-mentioned switch when the motor-controlling switchis moved to ottposition,

9. In combination, a controlling switch rotatable always in the samedirection and having an off-position and a plurality of operativepositions, operating means for said switch, controlling means forautomatically energizing said operating means to move said switch stepby step at prede termincd intervals from off-position to the directionand Copies of this patent may be obtained for several operativepositions, and means forenergizing said operating means independently ofsaid controlling means to move said switch from the last operativeposition to off-position. v

10. In combination, a controlling switch rotatable always in the samedirection and having an off-position and a plurality of operativepositions, an operating magnet, ratchet connections between said magnetand said switch, controlling means for automatically energizing saidmagnet a predeterminednumber of times corresponding to the number ofoperative positions of said switch at predetermined intervals, and meansfor energizing. said magnet independent-ly of said controlling means.

11. In combination, .a controlling switch having, ofl', starting, andrunning positions, an operatingmagnet for said switch, ratchetconnections between said magnet and said switch, a--c0ntr0lling magnet,means actuated by thelmovement of the core'of said controlling-magnetwhen energized for closmg the circuit of the operating magnet tomove'saidswitch from ofi to starting position,-means for automaticallybreaking the circuit of the controlling magnet when said switch T ismoved means actuated by the movement of-the core of the controllingmagnet when deenergized for breaking and then again closingthecircuit ofthe operating magnetvto shift said switch to running position, and meansfor retarding said movement of said core.

12. In combination, a switch rotatable always in the same direction andhaving an off-position and a plurality of operative positions, operatingmeans adapted to move said switch step by step, controlling meansadapted when actuated to energize said operating means automatically apredetermined number of times at predetermined intervals, means forenergizing said operating means. independently of said controllingmeans, and means for automatically breaking each of said electriccircuits when the switch is shifted.

. 13. In combination, a controlling switch having oil, star-ting andrunning positions, an electromagnetic controlling device for said switcharranged to close an electriccir cuit to. automatically shift saidswitch from off to starting position and after a predetermined intervalto close another circuit to shift the switch to runningposition, andmeans controlled .by said electromagnetic device whereby said switch isautomatically shifted from running to off position,

In witness whereof, I have hereunto set my hand this 29th day ofNovember, 1905,

BENJAMIN B. HULL, HELEN Onrom).

five cents each, by addressing the Commissioner of Patents-j Washington,D. C.

Correction in Letters PatentN0.1,064.228.

BEST AVAILABLE COP:

it is hereby certified that in Letters Patent i\'0. 1,064,228, grantedJune it), 1913, upon the application of Charles D. Knight, ofSchenectady, New York, for an improvement in AutomaticStnrtiugfiwitehes, an error appears in the printed specificationrequiring correction as follows: Page 2, line 115, for the word if" readand that the said Letters Patent should be read with this correctiontherein that the sznne may conform to the record of the ease in thePatent Oliiee.

Signed and sealed this 22nd day of July, A. D., 1913.

C. C. BILLINGS,

Acting Commissioner of Patents.

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